Effect of Diode Laser Office Bleaching on Mineral Content and Surface Topography of Enamel Surface: An SEM Study

To assess the effects of different bleaching procedures on the mineral component and surface topography of the enamel using scanning electron microscope (SEM) and energy-dispersive X-ray spectrometry (EDX).

Forty samples of approximately 3 × 3 mm size from the coronal portion of 20 extracted human anterior teeth were obtained. The samples were divided into two control groups and three experimental groups. In group I or positive control (n = 5), no bleaching or phosphoric acid treatment to the enamel surface was done. Group II samples or negative controls (n = 5) were treated with 37% phosphoric acid. In group III (n = 10), the tooth was treated with 35% hydrogen peroxide (HP) without any activation. Group IV (n = 10) was treated with 37.5% HP with LED light activation and group V (n = 10) was treated with 45% HP with diode laser activation. The calcium (Ca) and phosphorus (P) levels of each sample were measured using an EDX system prior to bleaching treatments. All the samples were again subjected to the EDX analysis after the bleaching treatment and two samples (after EDX analysis) from each group were subjected to the SEM analysis.

No significant difference was seen in phosphorus levels before and after the bleaching. However, significant increase in calcium levels was observed after bleaching activated with LASER and LED light. The SEM observations revealed maximum surface alterations on the enamel after chemically activated bleaching.

The LASER-activated bleaching agent seems to be more surface-friendly and less time-consuming as compared to other bleaching systems.

Suresh S, Navit S, Khan SA, et al. Effect of Diode Laser Office Bleaching on Mineral Content and Surface Topography of Enamel Surface: An SEM Study. Int J Clin Pediatr Dent 2020;13(5):481-485.